When a crime occurs, most people would agree that any method available should be used to catch the guilty person. Since 1986, forensic scientists have had a powerful new tool in their arsenal: DNA fingerprinting. From a drop of blood, a single hair, or a few skin cells left at a crime scene, technicians can produce the DNA sequence of the person who left it behind. Find a suspect with DNA that matches, and you've found your criminal. This sounds, at first, like a nearly perfect investigative tool. Critics, however, caution against relying too much on the technique. Are the risks, they wonder, worth the rewards? What about our right to privacy when it comes to the very thing that makes us who we are?